Flow propelled sewer or pipe threader



April 18, 1961 K. M. LITTLEFIELD 2,980,399

ELow PROPELLED sEwEE 0R PIPE TEEEADER Filed June 50, 1958 IN V EN TOR.

A TTORNE YS United States Kendall M. Littlefield, 1332 11th Ave. N.,

' Moorhead, Minn.

Filed June 30, 1958, Ser. No. 745,353 l1 Claim. (Cl. 254-134.4)

My invention relates to devices for the threading of sewer pipes and the like between spaced outlets, as a preliminary step to the cleaning of such pipes. j With the passage of time, residue laccumulates in the bottoms of sewers. This residue must periodically be cleaned out to prevent total clogging. Such cleaning requires that heavy ropes or cables be extended through the sewer pipes between spaced outlets, conventionally known as manholes. Cleaning buckets are attached to such ropes or cables; and the task of threading them through such pipes has always been a time consuming, di'icult and objectionable one.

The primary object of my invention is the provision of a novel device for relatively quickly and efficiently threading such sewer pipes initially with relatively exible rope for the subsequent attachment thereto and theading through the sewer pipe of a heavy duty rope or ca le.

A further object of my invention is the provision of a device of the class immediately above described which may be propelled through the sewer by means of fluid under pressure projected thereagainst from the end of a hose or the like, and to this end I provide an elongated buoyant core-like body having a plurality of axially spaced exible resilient discs thereon, said discs projecting radially outwardly therefrom in concentric relationship thereto and being of a diameter only slightly less than the diameter of the sewer pipe or the like through which they are intended to be forced.

A still further object of my invention is the provision of a device o-f the class immediately above described wherein the buoyant core-like body tapers progressively from its rear end to its front end, whereby the discs (of uniform diameter) are progressively more flexible toward the forward end and thus offer progressively less resistance to accumulated material in the bottom of the sewer pipe, from the rear end of the core to the front end thereof.

A further object of my invention is the provision of a device of the class above described which is inexpensive to produce and which is relatively simple and easy to install and remove from a given section of sewer pipe.

A still further object of my invention is the provision of a device of the class described which is rugged and durable in construction.

The above and still further objects of my invention will become apparent from the following detailed specication, appended claim and attached drawings.

Referring to the drawings wherein like characters indicate like parts throughout the several views:

Fig. l is a fragmentary view in vertical section of a manhole and sewer pipe, showing my novel device in side elevation in operation therein, and its method of use;

Fig. 2 is a View in side elevation of my novel device;

Fig. 3 is a View in vertical section of the structure of Fig- 1;

Fig. 4 is a view in rear end elevation; and

arent' ige Fig. 5 is an enlarged View in section of a portion of Fig. 1 and showing one of the flexible discs thereof in operation in passing over of 'an obstruction.

Referring with greater particular-ity to the drawings, the numeral 1 indicates an elongated body which preferably and as shown tapers from its rear end portion 2 to its front end portion 3 and is formed to provide a plurality of axially aligned sections 4. The body 1 .is formed from wood or other relatively light-weight buoyant material, for a purpose which will hereinafter be come apparent. Extending axially through the several core sections 4 s a clamping rod 5 having a threaded, nut-equipped forward end 6 and a ange-equipped rear end 7. Rearwardly of the flange 7 is a loop-equipped extension 8 for the reception of a rope or the like 9 to be threaded through a sewer pipe A, as indicated in Fig. l.. Also received on the clamping rod 5 and interposed between the sections 4 are a plurality of exible resilient discs 10 formed from molded rubber or the like. It will be noted that the rearmost disc 16 is interposed between the rear end portion 11 and the clamping flange 7 carried by the clamping rod 5. In this manner the discs 10 may be quickly replaced in the event of excessive Wear thereon due to use.

The use of my novel device is illustrated in Fig. 1. As there shown, the operator climbs down into the manhole B and manually inserts my novel device into the sewer pipe A with the tapered body 1 extending axially of the pipe A. Note that a exible cord or rope 9 is secured to the loop 8 on the rear end portion of the clamping rod 5. Also note that the diameter of the flexible resilient discs l@ is somewhat smaller than the diameter of the pipe A, preferably about two inches smaller than a conventional sewer pipe in which it is to be used. With this arrangement, the discs 10 rest upon the accumulated material Y in the bottom of the sewer pipe A and either frictionally engage or come close to the inner surface A of the pipe A, so as to limit or restrict the ilow of iluid under pressure thereabout. Thus, when fluid under pressure emanating from the end of a hose 12 is directed against the rear surface 13 of the rearmost disc 10, it imparts a driving force to the core 1. The water or other duid escaping between the peripheral edge of a given disc and the inner surface A of the pipe A is temporarily impeded and caused to accumulate between said disc 10 and the next disc 10 immediately forwardly thereof. This accumulation of fluid encompasses, at least in part, the buoyant body 1, thereby reducing the frictional engagement of the device upon the accumulated material Y.

Another important feature of my invention resides in the relative transverse thickness or diameter of the forwardly tapered buoyant body 1 with respect to the diameter of the several liexible resilient discs 10, longitudinally spaced thereon. Thus it is the foremost disc 10 which initially engages the accumulated material Y within the sewer pipe A. Consequently, in order to pass thereover, such disc 1t) must ex more easily than those rearwardly disposed with respect thereto. Therefore, I have found that the diameter of the most forwardly disposed disc 10 should be not las than three times that of the diameter of the core 1 immediately adjacent thereto, whereas the diameter of the most rearwardly disposed disc 10 is most eicient when it is only one-third greater than thecore 1 adjacent thereto. Fig. 5 illustrates the exible resilience of the rubber-like discs 19 in passing over a high point in the accumulated material Y in the pipe A. Fig. 5 also shows the small spacing between the peripheral edges 10a of the discs 10 and the inner surface A' of the pipe A which permits sufficient water under pressure from the hose 12 to accumulate between the discs 10, thereby permitting the water to exert a forward force on' each of the discs 10 in driving of my novel dyice from one manhole B to another manhole B. After lthis has been accomplished, ofcourse the corel with discs 10 'attached thereto isy remoyedand a'heavierworkrope or cable is attached to therrope 9fjand pulled throughxthe -spaced manholesB andconnected sewer pipes A.v

My inventionhas been thoroughly tested andfouwn'd topbe completely satisfactory for thefaccomplishment of theabove objects and -while I have-shown a `preferred r -embodiment thereof;Y VWish it to be'specic'allyunder- V'stoodrthat same is capable of vmodilcation Without de- Vparture from the scope and at` resilient ilexible^discs attached thereto, the diam- 'eters ofsad discs beingslghtly less than the diameter Y ofthe main in whichlthe device is being used, the core VVtapering from its. rearward end toward its gforward end nso that the unsupported `Vareas of the foremost disc is materially greater than that of subsequent rearward discs to permit greater exing ofi Said foremost discfwhereby to pass more easily over silt and Vobstructions in said main and reducedrag therein, said rearmost disc being exposed tothe full force of ruid pressure for driving said device through theV main, and me'ns at the larger end of the core for attaching a cable to'be drawn through the main,

References Citedrin the kiile of this patent UNTTED STATES PATENTS 55265535290 f rHowell "oct. 3, '1882 387,410 Gillette Aug. 7, 1888 920,455 Greenan May 4, 1909 934,520,4 Greenan v..,..., Sept. 21, 1909 979,899/ Steigleder' Dec. 27, 1910 1,382,587 A Withycor'ube.'.'L` June 2.1, 1921 731,297 Y OTHER REFERENCES- ;Electrical'World, R. L. Dodd, June 271117928, vol. 91, page 1334. 'v f Y 

